Furthermore, the ASAE (200 μg/mL) and arecoline (10 μg/mL) could significantly upregulate the mRNA expression of the c-jun proto-oncogene in oral mucosal fibroblasts, indicating that persistent induction of c-jun proto-oncogene by the areca nut and arecoline may be one of the mechanisms for oral squamous cell carcinoma [19, 20]. Here, JUN is linked to oral cavity squamous cell carcinoma.